package com.mobileclient.app;    
    
import java.io.File;    
import java.io.FileOutputStream;    
import java.io.PrintWriter;    
import java.io.StringWriter;    
import java.io.Writer;    
import java.lang.Thread.UncaughtExceptionHandler;    
import java.lang.reflect.Field;    
import java.text.DateFormat;    
import java.text.SimpleDateFormat;    
import java.util.Date;    
import java.util.HashMap;    
import java.util.Map;    
    
import android.content.Context;    
import android.content.pm.PackageInfo;    
import android.content.pm.PackageManager;    
import android.content.pm.PackageManager.NameNotFoundException;    
import android.os.Build;    
import android.os.Environment;    
import android.os.Looper;    
import android.util.Log;    
import android.widget.Toast;    
    
/**  
 * UncaughtException处理类,当程序发生Uncaught异常的时候,有该类来接管程序,并记录发送错误报告.  
 *   
 * @author user  
 *   
 */    
public class CrashHandler implements UncaughtExceptionHandler {    
        
    public static final String TAG = "CrashHandler";    
        
    //系统默认的UncaughtException处理类      
    private Thread.UncaughtExceptionHandler mDefaultHandler;    
    //CrashHandler实例     
    private static CrashHandler INSTANCE = new CrashHandler();    
    //程序的Context对象     
    private Context mContext;    
    //用来存储设备信息和异常信息     
    private Map<String, String> infos = new HashMap<String, String>();    
    
    //用于格式化日期,作为日志文件名的一部分     
    private DateFormat formatter = new SimpleDateFormat("yyyy-MM-dd-HH-mm-ss");    
    
    /** 保证只有一个CrashHandler实例 */    
    private CrashHandler() {    
    }    
    
    /** 获取CrashHandler实例 ,单例模式 */    
    public static CrashHandler getInstance() {    
        return INSTANCE;    
    }    
    
    /**  
     * 初始化  
     *   
     * @param context  
     */    
    public void init(Context context) {    
        mContext = context;    
        //获取系统默认的UncaughtException处理器     
        mDefaultHandler = Thread.getDefaultUncaughtExceptionHandler();    
        //设置该CrashHandler为程序的默认处理器     
        Thread.setDefaultUncaughtExceptionHandler(this);    
    }    
    
    /**  
     * 当UncaughtException发生时会转入该函数来处理  
     */    
    @Override    
    public void uncaughtException(Thread thread, Throwable ex) {    
        if (!handleException(ex) && mDefaultHandler != null) {    
            //如果用户没有处理则让系统默认的异常处理器来处理     
            mDefaultHandler.uncaughtException(thread, ex);    
        } else {    
            try {    
                Thread.sleep(3000);    
            } catch (InterruptedException e) {    
                Log.e(TAG, "error : ", e);    
            }    
            //退出程序     
            android.os.Process.killProcess(android.os.Process.myPid());    
            System.exit(1);    
        }    
    }    
    
    /**  
     * 自定义错误处理,收集错误信息 发送错误报告等操作均在此完成.  
     *   
     * @param ex  
     * @return true:如果处理了该异常信息;否则返回false.  
     */    
    private boolean handleException(Throwable ex) {    
        if (ex == null) {    
            return false;    
        }    
        //使用Toast来显示异常信息     
        new Thread() {    
            @Override    
            public void run() {    
                Looper.prepare();    
                //Toast.makeText(mContext, "很抱歉,程序出现异常,即将退出.", Toast.LENGTH_LONG).show();    
                Looper.loop();    
            }    
        }.start();    
        //收集设备参数信息      
        collectDeviceInfo(mContext);    
        //保存日志文件      
        saveCrashInfo2File(ex);    
        return true;    
    }    
        
    /**  
     * 收集设备参数信息  
     * @param ctx  
     */    
    public void collectDeviceInfo(Context ctx) {    
        try {    
            PackageManager pm = ctx.getPackageManager();    
            PackageInfo pi = pm.getPackageInfo(ctx.getPackageName(), PackageManager.GET_ACTIVITIES);    
            if (pi != null) {    
                String versionName = pi.versionName == null ? "null" : pi.versionName;    
                String versionCode = pi.versionCode + "";    
                infos.put("versionName", versionName);    
                infos.put("versionCode", versionCode);    
            }    
        } catch (NameNotFoundException e) {    
            Log.e(TAG, "an error occured when collect package info", e);    
        }    
        Field[] fields = Build.class.getDeclaredFields();    
        for (Field field : fields) {    
            try {    
                field.setAccessible(true);    
                infos.put(field.getName(), field.get(null).toString());    
                Log.d(TAG, field.getName() + " : " + field.get(null));    
            } catch (Exception e) {    
                Log.e(TAG, "an error occured when collect crash info", e);    
            }    
        }    
    }    
    
    /**  
     * 保存错误信息到文件中  
     *   
     * @param ex  
     * @return  返回文件名称,便于将文件传送到服务器  
     */    
    private String saveCrashInfo2File(Throwable ex) {    
            
        StringBuffer sb = new StringBuffer();    
        for (Map.Entry<String, String> entry : infos.entrySet()) {    
            String key = entry.getKey();    
            String value = entry.getValue();    
            sb.append(key + "=" + value + "\n");    
        }    
            
        Writer writer = new StringWriter();    
        PrintWriter printWriter = new PrintWriter(writer);    
        ex.printStackTrace(printWriter);    
        Throwable cause = ex.getCause();    
        while (cause != null) {    
            cause.printStackTrace(printWriter);    
            cause = cause.getCause();    
        }    
        printWriter.close();    
        String result = writer.toString();    
        sb.append(result);    
        try {    
            long timestamp = System.currentTimeMillis();    
            String time = formatter.format(new Date());    
            String fileName = "crash-" + time + "-" + timestamp + ".log";    
            if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) {    
                String path = "/sdcard/crash/";    
                File dir = new File(path);    
                if (!dir.exists()) {    
                    dir.mkdirs();    
                }   
                
                FileOutputStream fos = new FileOutputStream(path + fileName);    
                fos.write(sb.toString().getBytes());    
                fos.close();  
               
            }    
            return fileName;    
        } catch (Exception e) {    
            Log.e(TAG, "an error occured while writing file...", e);    
        }    
        return null;    
    }    
}   